From ca35e8e7744d0b1ad2bf09fd8fb3cee17b749d8f Mon Sep 17 00:00:00 2001
From: Gabriel Kaszewski <gabrielkaszewski@gmail.com>
Date: Sat, 16 May 2026 10:55:58 +0200
Subject: [PATCH] feat(domain): add DomainError::UniqueViolation {field}

---
 crates/domain/src/errors.rs       | 2 ++
 crates/presentation/src/errors.rs | 3 +++
 2 files changed, 5 insertions(+)

diff --git a/crates/domain/src/errors.rs b/crates/domain/src/errors.rs
index fb8ac55..e3d6a29 100644
--- a/crates/domain/src/errors.rs
+++ b/crates/domain/src/errors.rs
@@ -10,6 +10,8 @@ pub enum DomainError {
     Forbidden,
     #[error("conflict: {0}")]
     Conflict(String),
+    #[error("unique violation on field: {field}")]
+    UniqueViolation { field: &'static str },
     #[error("invalid input: {0}")]
     InvalidInput(String),
     #[error("external service error: {0}")]
diff --git a/crates/presentation/src/errors.rs b/crates/presentation/src/errors.rs
index db1ec41..f0c1e38 100644
--- a/crates/presentation/src/errors.rs
+++ b/crates/presentation/src/errors.rs
@@ -27,6 +27,9 @@ impl IntoResponse for ApiError {
             }
             Self::Domain(DomainError::Forbidden) => (StatusCode::FORBIDDEN, "forbidden".into()),
             Self::Domain(DomainError::Conflict(m)) => (StatusCode::CONFLICT, m),
+            Self::Domain(DomainError::UniqueViolation { field }) => {
+                (StatusCode::CONFLICT, format!("{field} already taken"))
+            }
             Self::Domain(DomainError::InvalidInput(m)) => (StatusCode::UNPROCESSABLE_ENTITY, m),
             Self::Domain(DomainError::ExternalService(_)) => {
                 (StatusCode::BAD_GATEWAY, "external service error".into())